False success installing a package when MD5sum mismatched

[Ashrentum]

Binary package hint: apt

Machine: Xubuntu 7.10 (original kernel 2.6.22), AMD Turion64 x2

Particular problem:
Installing the flashplugin-nonfree packet. I get success doing it, but later flash doesn't work. After reinstalling again I check that the MD5sum mismatched but still the packet is marked as installed and successfully.

General problem:
I have seen the same problem for other packets.

Real problem:
Having apparently success when is not true. Bug in packet manager (synaptic, apt, whatever). When you couldn't install the packet due a MD5sum mismatch or another reason, you should see perfectly that there were a problem and you couldn't install the packet. This can get crazy a person because you see the program like installed when is not. Then maybe you try to install it again but the response is that you have it already installed when is not true.

This was terrible when I tried to get working flash in Firefox. ->Install missing plugins -> Install Flash Player -> Error you have it already installed!! ???

More problematic with Synaptic because maybe you never see the MD5sum mismatch.

This is not a duplicate of bug 173890

[Dara Adib (daradib)]

Marking as duplicate of bug 173890. See http://ubuntuforums.org/showthread.php?t=636397 for more information.

[Dara Adib (daradib)]

I understood your bug, its not a duplicate. Sorry. The error with the flashplugin-nonfree is bug 173890. But yes, you have a good point, it should not seem that the package is installed. But this may have to do more with the individual packages than apt itself, although I am unsure.

[Ashrentum (jmcejuela)]

I answer to you, thinking you are the administrator for this. I saw that
there are some other packets with the same problem, for this I think is a
general problem for apt.

On 11/12/2007, Cyrus Jones <email address hidden> wrote:
>
> I understood your bug, its not a duplicate. Sorry. The error with the
> flashplugin-nonfree is bug 173890. But yes, you have a good point, it
> should not seem that the package is installed. But this may have to do
> more with the individual packages than apt itself, although I am unsure.
>
> ** Changed in: apt (Ubuntu)
> Status: New => Confirmed
>
> --
> False success installing a packet when MD5sum mismatched
> https://bugs.launchpad.net/bugs/175255
> You received this bug notification because you are a direct subscriber
> of the bug.
>

--
Juan Miguel Cejuela

[Dara Adib (daradib)]

I don't think this would be considered a duplicate as this bug focuses on package manager/Synaptic/apt-get's marking of a package as installed, while Bug 144042 focuses on the success Firefox gives when the wizard is used. At least this is my interpretation of this bug. I will unmark as a duplicate, please remark as duplicate if I am incorrect.

[Bryan Silverthorn (bcsilverthorn)]

Ok, that's a good point. (Although it's worth noting that #14402 will be fixed by fixing this bug, so there's significant overlap.)

[Roberto Sarrionandia (rbs-tito)]

This is a duplicate, it is a different symptom of the same problem.

If you have anything you feel you can add please put it in bug 173890

Thank you for taking the time to report this.

[Dara Adib (daradib)]

I apologize, but I insist on checking Bug 182468, which accurately describes the problem.
"The problem with bug #173890 seems to be a md5sum mismatch, and
The problem with bug #182498 seems to be the Synaptic Packet Manager is not detecting that the program has not installed."
Please read that Bug 182468 and its comments.

[Saivann Carignan (oxmosys)]

This bugs is in the flashplugin-nonfree package which does not tells synaptic that the installation script failed so even if the script print "md5 missmatch", it does not mean anything to synaptic if the script finally tells to synaptic that it was executed correctly. I set the package to flashplugin-nonfree

[Saivann Carignan (oxmosys)]

This bug has not been fixed with the update for bug 173890. It can still be reproduced.

[Saivann Carignan (oxmosys)]

Apparently, this bug can't be fixed so easily. Use of md5sums are very important and can't be dropped, and when there's a md5sum missmatch, if the package return 1 and tells synaptic that the installation failed, synaptic will automatically try to reinstall it each time it will install another package. The only way I can see to fix this would be to distribute a flashplugin-nonfree source package that contains the upstream flash player tarball. This way, flash player updates won't affect ubuntu users and the package would always install properly. This solution may require canonical to speak with adobe to gain right to distribute flash. I opened a Wishlist bug for that matter : bug 189790

[Saivann Carignan (oxmosys)]

Unfortunately, this idea does not seem to be feasible from now, so we should search for another solution for that bug.

[Dara Adib (daradib)]

Yes, I looked at the wishlist bug via flashplugin-nonfree package notifications and then came here. I agree, we should contact Adobe and tell them about this issue. At the very minimum, they can avoid updating the flash plugin without renameing the file (to reflect the version). It would be ideal in this sense if they would keep older versions of flash (as separate downloads). However, permission to distribute would be even better as it could solve this problem as well.

[Saivann Carignan (oxmosys)]

I contacted Adobe and they suggest that linux users ask for this at www.adobe.com/go/wish
To every ubuntu users that does not want flashplugin-nonfree to get into problems at each update of flash from adobe, I suggest to ask Adobe to provide permanent links for all recent linux version of flash.

[Horacio Castillo (castillh)]

I don't have any experience with writing system software, so if this suggestion is really bad for some reason, I apologize in advance. I also apologize for not providing a patch to implement my suggestion, I wouldn't know how to code it.

The problem seems to be that the installer script (flashplugin-nonfree) assumes that the available version of the external package (Adobe flash) is always the same, and therefore the expected value of the md5sum is hardcoded. However, the external package does change, because Adobe changes it, and the hardcoded md5sum becomes unsynchronized with the only easily available version of the package.

There seem to be two basic ways to fix the problem:

i) Convince Adobe to make older versions of the package available at fixed locations, and modify flashplugin-nonfree so that it downloads always a fixed version (possibly not the latest one).

ii) Modify flashplugin-nonfree so that it can (almost) always successfully install the latest version of the package.

As it was mentioned before, option (ii) is not optimal because newer versions of Flash may break other packages, so (i) would be better, but we don't have that yet.

As a stop-gap measure, I propose the following way to make (ii) work: instead of hard-coding the "correct" value of the md5sum in flushplugin-nonfree, store it in a webpage and have flashplugin-nonfree read it from there.

In this way we would have the benefits of checking the md5sum to make sure the file being downloaded from an external source is the correct one, but also the md5sum could be easily kept updated by the flashplugin-nonfree package maintainer without needing to go through the complicated process of generating an updated version of the
package, and getting it in the repositories.

[Dara Adib (daradib)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. This particular bug has already been reported and is a duplicate of bug 144042, so it is being marked as such. Please look at the other bug report to see if there is any missing information that you can provide, or to see if there is a workaround for the bug. Additionally, any further discussion regarding the bug should occur in the other report. Feel free to continue to report any other bugs you may find.